Re: noop comparator for qsort

From: kevin.bagust (kevin.bagust_at_ntlworld.com)
Date: 11/14/04 

Date: Sun, 14 Nov 2004 19:06:38 GMT

In article <20041114191540.0a12ca75@harpo.marx>,
   Trent Buck <NOSPAMfubarbaz@bigpond.com> wrote:
> The fourth argument is a comparator that returns `an integer less than,
> equal to, or greater than zero' depending on the ordering of its
> arguments.

> If I don't care about the order and simply want qsort() to run as
> quickly as possible, how should the comparator be defined?

How about comparing the pointers rather than the items pointed to? So
something like this:

int compare( void *x, void *y )
{
  if ( x < y ) {
    return -1;
  }
  else if ( y < x ) {
    return 1;
  }
  else {
    return 0;
  }
}

Kevin Bagust.

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